Descriptions

A newly described funguslike organism named Phytophthora ramorum was
discovered in 1993 to cause leaf blight, stem canker, and tip dieback on nursery-grown rhododendrons and viburnums in Germany and the Netherlands. At about the same time, many tanoaks (Lithocarpus densiflorus) and oaks (Quercus sp.) in the San Francisco Bay Area were dying from a new disease. The
cause of this “sudden oak death” was also Phytophthora ramorum.